A database, such as relational database or an object-oriented database, or an other type of data management system may be used for the administration of data processed by a computer system running one or more application programs. Some data in the data management system may be incorrect because data is duplicated in the data management system. Data may be duplicated when two or more identical records exist in the data management system, when two or more records that represent the same entity exist in a data management system in which only one record for a particular entity is permitted, or when two records exist that incorrectly represent the same entity or event even when the records are not identical and more than one record for a particular entity or event is permitted. Duplicated data or incorrect data may be removed from the data management system to improve the accuracy of the data stored.